CVE-2005-0021

CVE-2005-0021 is a high-severity vulnerability in University Of Cambridge Exim with a CVSS 2.0 base score of 7.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

Multiple buffer overflows in Exim before 4.43 may allow attackers to execute arbitrary code via (1) an IPv6 address with more than 8 components, as demonstrated using the -be command line option, which triggers an overflow in the host_aton function, or (2) the -bh command line option or dnsdb PTR lookup, which triggers an overflow in the dns_build_reverse function.

Frequently asked questions

What is CVE-2005-0021?
Multiple buffer overflows in Exim before 4.43 may allow attackers to execute arbitrary code via (1) an IPv6 address with more than 8 components, as demonstrated using the -be command line option, which triggers an overflow in the host_aton function, or (2) the -bh command line option or dnsdb PTR lookup, which triggers an overflow in the dns_build_reverse function.
How severe is CVE-2005-0021?
CVE-2005-0021 has a CVSS 2.0 base score of 7.2, rated high severity.
Is CVE-2005-0021 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2005-0021?
CVE-2005-0021 primarily affects University Of Cambridge Exim. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2005-0021?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2005-0021 published?
CVE-2005-0021 was published on 2005-05-02 and last updated on 2026-06-16.

References

Affected products (3)

More vulnerabilities in University Of Cambridge Exim

All CVEs affecting University Of Cambridge Exim →